{
  "abstract": "Strengthening light-matter coupling has become a central challenge in cavity quantum electrodynamics (QED), enabling ultrafast gate operations, qubit protection, and deterministic nonlinear optics. As the coupling increases, even the simplest configuration, a two-level atom interacting with a quantized field, requires careful treatment, as exemplified by the gauge-invariant quantum Rabi model (QRM). Here we propose a magnetic graph model for single-atom cavity QED, which enables the interpretation of quantum dynamics across the ultrastrong coupling regime through graph connectivity. We demonstrate that the generalized QRM maps onto a complex bipartite graph of identical sites under Floquet boundary conditions. This framework captures the crossover from weak to deep-strong coupling via a single metric: the cost of disconnecting a nonmagnetic subgraph. We examine the mechanism underlying this connectivity transition, establishing phase frustration induced by subgraph topology as the primary driver. Scalable to many-body systems, this approach bridges graph theory and cavity QED, revealing highly complex-graph dynamics even in the simplest setting.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Science Advances 12, eaee5566 (2026)",
  "arxiv": "2607.04736",
  "author_total": 3,
  "authors": [
    {
      "name": "Sunkyu Yu"
    },
    {
      "name": "Xianji Piao"
    },
    {
      "name": "Namkyoo Park"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dgnap20z1fnyw.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.04736",
  "fulltext_url": null,
  "id": "dgnap20z1fnyw",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.04736",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "quant-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2607.04736",
  "pmcid": null,
  "pmid": null,
  "published": "2026-07-06",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dgnap20z1fnyw.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2607.04736",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.04736"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Magnetic graphs for cavity quantum electrodynamics",
  "title_text": "Magnetic graphs for cavity quantum electrodynamics",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/dgnap20z1fnyw",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1126/sciadv.aee5566",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}